The present invention relates to siphons adapted for discharging liquid from a tank at the end of a periodic cycle and, in particular, to a consistent siphon which begins each cycle under substantially equivalent conditions with regard to liquid levels within the siphon. In addition, a trigger mechanism is provided to initiate discharge of the liquid when the level thereof reaches an adjustable but predetermined height. Consistency of operation under varying tank liquid levels and, in particular, varying driving heads is also ensured by concentrating liquid head losses in the siphon toward the outlet thereof. A particularly efficient and compact siphon is embodied in a spiral or conchoidal shape and multiple siphons can be interconnected by the trigger mechanism to initiate siphon action, that is vigorous liquid discharge, simultaneously.
Siphons, according to the present invention, are used to develop a relatively large directional flow of liquid over a relatively short period of time in order to flush debris from troughs and floors of livestock enclosures. Since moving parts tend to fail in such devices, the siphons are designed without such parts, depending for operation on the forces of gravity, liquid hydraulic pressures and strategic placement of parts, such that sudden discharge of liquid from the siphon is triggered at the appropriate time, without allowing the siphon to become "waterlogged", that is discharge liquid slowly and continuously. Such siphons should be able to function under varying heads and varying liquid output requirements, so that a single design can be used for alternative services, rather than producing different designs for each service; this is especially true for driving heads. In conventional siphons a particular design often functions properly under only one general head condition. The siphon should be efficient and concentrate head losses therein toward the outlet thereof, thus being able to operate with an extremely low driving head.
Many conventional siphons require elaborate siphon break mechanisms to ensure sufficient liquid remains therein to fill liquid traps for succeeding discharge cycles. Such devices are inconsistent in operation and are often easily plugged by debris, causing over or under filling of liquid traps and consequently causing flooding or waterlogging of the siphon, which requires manual attention to correct. In addition many conventional devices are bulky in design and shape.